Corrugated sheet flashing



June 6, 1967 H. T. RICHARDSON CORRUGATED SHEET FLASHING Filed Jan; 8,1965 INVENTOR. HARLOW T RICHARDSON ATTORNEYS United States Patent FiledJan. 8, 1965, Ser. No. 424,416 4 Claims. (Cl. 52-90) This inventionrelates to flashing for cojoined corrugated sheets and, moreparticularly, to improved means for closing the juncture between amargin of one sheet which is transverse to its corrugations and thecorrugated face of another sheet which extends across that margin.

Corrugated sheets serve quite well in various structures as siding,roofing and so on, but because of the crests and vales of thecorrugations with which they are formed special measures must often betaken to seal junctures where the corrugated face of one such sheetextends across the margin of another sheet which is transverse to itscorrugation. If this margin is simply squared off in the usual manner itextends across the corrugated face of the other sheet without closingthe vales and crests of both sheets. For example, a building ofcorrugated sheets commonly has a horizontal eave where a roofing sheetslopes down to and overhangs a vertical siding sheet. The corrugationsof both sheets are usually disposed perpendicular to their juncture atthe eave, and therefore the margin of the siding sheet at the junctureis transverse to its corrugations and the corrugated underside of theroofing sheet lies over that margin. Flashing for sealing the junctureis provided on the outside of the building underneath the eave and itoften takes the form of sheet metal or lead strips fitted into theopening corrugations of the underside of the roofing sheet and theoutside of the siding sheet along the eave.

In United States Patent No. 2,641,340, alternate flashing means isdescribed which involves mitering the siding sheet along theaforementioned margin oppositely to the slope of the roofing sheet at anangle equal to 45 minus half the slope of the roof, and aligning thecrests of both the roofing and siding sheets as viewed from the outsideof the building. This mitering imparts a wavy form to the margin of thesiding sheet at the eave which generally conforms to the verticalsection of crests and vales of the corrugations on the underside of theroofing sheet otherwise requiring some more cumbersome flashingmaterial. While this particular mitering concept represents a certainadvance in flashing design for the eave of a corrugated structure, it isnot without significant disadvantages. For one thing, each corrugatedsheet has a smoother face on what is to be its outside surface wheninstalled and this face is uppermost when the sheet emerges fromproduction and is shipped. The prior art mitering concept often requiresthat each sheet be turned upside down from this position to permittrimming of the angle cut in the factory and then reversed so that thesmooth side is uppermost for shipping. Another disadvantage of the knownmitering concept is that, since the wavy margin imparted to the sidingsheet only approximates a fit with the overlying corrugated face of theroofing sheet, caulking must be applied on the outside of the buldingalong the juncture at the cave to complete the seal, and the caulkingcom pound must adhere within the downwardly directed acute angle betweenthe sheets to the underside of the roofing sheet and also against theexterior vertical face of the siding sheet where no underlying supportfor the compound is provided.

It is the purpose of the present invention to improve upon the miteringprinciple described in the aforementioned patent. In particular, theobject of this invention is to permit the mitered surfaces to be trimmedin the factory without turning the sheets upside down as noted 3,323,261Patented June 6, 1967 above, and to provide a kind of shelf forsupporting the caulking compound where it can complete the seal on theoutside of the juncture along the eave.

Broadly stated, the subject of the invention is a cojoined pair ofcorrugated sheets of the same corrugated configuration having crests andvales disposed substantially perpendicular to a juncture between thesheets. The first sheet extends beyond the margin of the second sheetwhich is transverse to the corrugations of the second sheet and definesan acute angle with the second sheet. In accordance with the inventionthis juncture is improved in that the crests of the first sheet arealigned with the vales of the second sheet as viewed from the acuteangle side of the juncture, and the margin of the second sheet ismitered at an angle substantially parallel to a plane bisecting theacute angle between the sheets. In particular, the mitered margin of thesecond sheet is in a plane angled relative to a perpendicular from thesecond sheet at 45 plus half the complement of the acute angle.

Unlike the priorart mitering approach, the invention involves aligningthe crests on one sheet with the vales (instead of the crests) of theother sheet as viewed from what is usually the outside of a structure,cutting the mitered surface in a direction which is generally the sameas (rather than opposite to) the slope of the roofing sheet, anddisposing the plane of the miter relative to the perpendicular at anangle of 45 plus (instead of minus) half the slope of the roofing sheet.The effect of these three basic departures from the prior art is toprovide a cut which can be trimmed in the factory without even onceturning each sheet upside down. Also, it provides angled shelf means onthe outside of the juncture at the eave which lends support to caulkingcompound applied to seal the juncture. In addition, the caulkingcompounds can be disposed in this shelf means generally flush with theface of siding sheet, thus improving the appearance of the structure.

A preferred embodiment of the invention is described hereinbelow withreference to the accompanying drawing, wherein FIG. 1 is a fragmentaryperspective of a horizontal eave with flashing in accordance with theinvention;

FIG. 2 is an enlarged fragmentary section taken along the line 2-2 ofFIG. 1; and

FIG. 3 is a fragmentary section taken along the line 3-3 of FIG. 2.

In this particular form of the invention, a corrugated roofing sheet 10and siding sheet 12 are cojoined along the cave of a building. As viewedfrom the outside of the building, the roofing sheet 10 is formed withcrests 14 and vales 16 of standard configuration and the siding sheet 12is formed with similar crests 18 and vales 20. The crests and valves 14and 16 of the roofing sheet 10 and the crests and vales 18 and 20 of thesiding sheet 12 are all disposed perpendicular to a horizontal juncturebetween the sheets, which in effect is along the eave of the building.The roofing sheet 10 sloped downwardly at an angle a from the horizontalwhich is most often 18 because the slope of typical corrugated roofingis 4 in 12. The roofing sheet 10 thus slopes down to and over thehorizontal margin of the siding sheet 12 which is transverse to thecrests 18 and vales 20 of the corrugated siding sheet 12. Together theroofing sheet 10 and siding sheet 12 define an acute angle 12 which inthis example is on the outside of the building under the eave. The acuteangle 12 is the complement of the slope angle a because together theyequal The upper margin of the siding sheet 12 at the juncture with theroofing sheet 10 would leave openings defined by the crests and vales ofthe corrugations of both the roofing sheet 10 and the siding sheet 12 ifthe margin of the siding sheet 12 were simply squared off perpenadicular to its plane in the usual manner. The depth of these openings isindicated in FIG. 2 by the dimension x, and it is here that sheet metalor lead has been used to cover and seal the juncture in certain priorart approaches to the problem of flashing. In accordance with theinvention no extra flashing elements of this sort are required. Asviewed from the outside of the building, ie the acute angle b side ofthe juncture, the invention provides that the crests 18 of the sidingsheet 12 be aligned with the vales 16 of theroofing sheet 10, as isshown most clearly in FIGS. 1 and 2. In FIG. 3, which is a section ofthe juncture viewed from the inside of the building opposite the acuteangle 12, the rear face of these crests 18 and vales 20 of the sidingsheet 12 are seen, and of course they appear in reverse.

In addition, the invention provides that the horizontal margin of thesiding sheet 12 be formed with a mitered surface 22. This miteredsurface 22 is in a plane sloping downwardly toward the outside (or acuteangle side) of the juncture at a certain angle c relative to aperpendicular from the general plane of the siding sheet 12. Themitering angle is carefully chosen to best cover the juncture betweenthe sheets and 12 at the eave and it is equal to 45 plus half thecomplement of the acute angle b, which is the same as the slope angle aof the roofing sheet.

By mitering the upper margin of the siding sheet 12 in this fashion, awavy periphery is imparted to it as viewed in elevation (see FIG. 3) andthis conforms quite closely to the vertical section through thecorrugations of the roofing sheet 10. In no case will the .miteringangle 0 be less than 45. The face of the siding sheet 12 on the outsideof the building (on the left in FIG. 2) is the smooth face of the sheetwhich is disposed upwardly when the sheets emerge from production in thefactory, and the mitered surface 22 can be trimmed without turning eachof the siding sheets 12 upside down.

An advantage of particular importance is that, when the siding sheet 12is mitered as described, its thickness provides an angled shelf 24 onthe outside of the juncture for convenient and secure reception of puttyor other caulking compound 26 which may be applied under the eave toseal the juncture completely. In the aforementioned prior art miteredjuncture, no such shelf 24 is possible because the smooth outside faceof the siding sheet extends vertically upward to the underside of theroofing sheet and hence the caulking is provided with no underlyingsupport. Roofing sheets expand to a considerably greater extent due tomoisture absorbtion in use than their associated siding sheets becausethey are more exposed to precipitaation. As a result, there is relativemotion between the sheets along their juncture and this tends to crackand even dislodge caulking compound which is not securely applied.

It is to be understood that this new concept of a mitered juncturebetween corrugated sheets is not limited to a horizontal eave between adownwardly sloping roofing sheet and a vertical siding sheet asdescribed in the foregoing example. In the general sense the acute angleb is to be used as the reference side of the juncture for determiningthe direction of the mitered surface 22, and the acute angle b could beon the inside of a structure as well as the outside. Also, the upperface of the sheet 10 appearing in FIG. 2 could be on the inside insteadof the outside of the structure. It is equally possible that the sheets10 and 12 could both be vertical siding sheets which are notperpendicular to one another, or that the sheet 10 could extend underinstead of over the sheet 12. The scope of these and other evidentvariations in the invention is set forth in the following claims.

I claim:

1. In a cojoined pair of corrugated sheets of the same corrugatedconfiguration having crests and vales disposed substantiallyperpendicular to a juncture between the sheets, the first sheetextending beyond a margin of the second sheet which is transverse to thecorrugations of the second sheet and defining an acute angle with thesecond sheet, said juncture being improved in that (a) the crests of thefirst sheet are aligned with the vales of the second sheet as viewedfrom the acute angle side of the juncture;

(b) the margin of the second sheet is mitered at an angle substantiallyparallel to a plane bisecting the acute angle between the sheets; and

(c) the mitered periphery of the second sheet conforms closely to thecrests and vales of the first sheet along the juncture.

2. A cojoined pair of corrugated sheets according to claim 1 wherein themitered margin of the second sheet is in a plane angled relative to aperpendicular from the second sheet at 45 plus half the complement ofsaid acute angle.

3. In a cojoined pair of corrugated roofing and vertical siding sheetsof the same corrugated configuration having crests and vales disposedsubstantially perpendicular to a horizontal juncture between the sheets,the roofing sheet sloping down to and over a horizontal margin of thesiding sheet which is transverse to the corrugations of the siding sheetand defining an acute angle with the siding sheet, said juncture beingimproved in that (a) the crests of the roofing sheet are aligned withthe vales of the siding sheet as viewed from the acute angle side of thejuncture,

(b) the margin of the siding sheet is mitered in a plane slopingdownwardly toward the acute angle side of the juncture in a plane angledrelative to a perpendicular from the siding sheet at 45 plus half thecomplement of said acute angle; and

(c) the mitered periphery of the second sheet conforms closely to thecrests and vales of the first sheet along the juncture.

4. A cojoined pair of corrugated roofing and siding sheets according toclaim 3 wherein the mitered margin of the siding sheet forms slopingshelf means on the acute angle side of the juncture, and caulking meanssealing said juncture are at least partly supported on said shelf means.

References Cited UNITED STATES PATENTS 168,260 9/1875 Lassig 14741,375,402 4/1921 McAvoy 5290 2,330,819 10/1943 Faure et al. 52902,641,340 6/1953 Howe 52-90 2,664,177 12/1953 Hammitt et al. 52-90FOREIGN PATENTS 1,296,912 5/1962 France.

FRANK L. ABBOTT, Primary Examiner.

M. O, WARNECKE, Assistant Examiner,

1. IN A COJOINED PAIR OF CORRUGATED SHEETS OF THE SAME CORRUGATEDCONFIGURATION HAVING CRESTS AND VALES DISPOSED SUBSTANTIALLYPERPENDICULAR TO A JUNCTURE BETWEEN THE SHEETS, THE FIRST SHEETEXTENDING BEYOND A MARGIN OF THE SECOND SHEET WHICH IS TRANSVERSE TO THECORRUGATIONS OF THE SECOND SHEET AND DEFINING AN ACUTE ANGLE WITH THESECOND SHEET, SAID JUNCTURE BEING IMPROVED IN THAT (A) THE CRESTS OF THEFIRST SHEET ARE ALIGNED WITH THE VALES OF THE SECOND SHEET AS VIEWEDFROM THE ACUTE ANGLE SIDE OF THE JUNCTURE; (B) THE MARGIN OF THE SECONDSHEET IS MITERED AT AN ANGLE SUBSTANTIALLY PARALLEL TO A PLANE BISECTINGTHE ACUTE ANGLE BETWEEN THE SHEETS; AND (C) THE MITERED PERIPHERY OF THESECOND SHEET CONFROMS CLOSELY TO THE CRESTS AND VALES OF THE FIRST SHEETALONG THE JUNCTURE.